This power cable fits your "Trio-Ultra" and the "Neo-SD_PRO-power supply".
 
When you buy a Trio-Ultra-PSU or a NeoSDPro-PSU, you choose "with" or "without" power cable because many of our customers have this very common power cable laying around.  But RGC offers this part as a separate purchase just in case you bought your Trio-Ultra without the power cable and now you decided you need one.
Fits the Trio-Ultra*
Fits the NEO-SDPRO-PSU